1. Field of the Invention
This invention relates to a telephone set usable as an acoustic coupler, comprising an acoustic coupler for facsimile communication, etc. and a telephone unit for telephone communication, which are made integral.
2. Related Background art
The conventional acoustic coupler is connected to, for example, a facsimile machine etc. and is used as a signal transmitter of a facsimile picture signal by being placed in contact with the handset of an ordinary telephone set for facsimile communication.
In a fixed type facsimile machine in which the acoustic coupler is not used, a telephone line is directly connected to the fixed type facsimile machine and therefore, it is necessary to provide a telephone set for calling another facsimile machine to be communicated with.
Accordingly, when a portable type facsimile machine is used as the fixed type facsimile machine, the user must provide not only an acoustic coupler but also a telephone set connected to a telephone line. However, there is no machine having both an acoustic coupler function and telephone function, and therefore, the user must always prepare both an acoustic coupler and a telephone set.